A man accused of beating to death three generations of the same family in their home has denied being the murderer.
David Morris said he lied to police to avoid being implicated
Former scrap dealer David Morris is accused of killing Mandy Power, her two children and their grandmother at their home in Clydach in June 1999.
The prosecution claimed after the "massacre," he washed his clothes before setting the house on fire.
When asked "Did you play any part at all in the murders?" the 44-year-old of Craig-cefn-parc, replied: "No".
Dressed in a dark suit and light-green shirt and tie and gold-rimmed glasses, he took to the witness stand on Thursday for the first time.
Mandy Power's siblings were in court for the defence opening
When the case was opened in May, the prosecution claimed the "clinching piece of evidence" against him was a metal chain found at the point of most extreme violence at the murder scene.
Mr Morris told the court that he had bumped into Ms Power in Clydach on Friday 25 June. He said he had invited himself to her home for a cup of coffee.
The jury of six men and six women were told that he had taken his broken chain from his pocket and left it on a work surface in the kitchen.
Lied to police
Mr Morris said he then went upstairs to have sex with Mandy Power.
Mr Morris then said he went to his parents' house, forgetting the chain he had left in Ms Power's kitchen.
The jury has already heard that he later lied to the police, denying that the gold chain belonged to him.
One witness previously told the court how Mr Morris bought a new chain and rubbed it in cement and damaged the clasp to make it look more like his old one.
Several fires were started in the house in Kelvin Road, Clydach
Mr Morris told the court that he had lied to the police because he did not want to implicate himself in the murders.
Prosecutor Patrick Harrington QC accused Mr Morris of lying about meeting Ms Power and having sex on the day before her death.
He claimed two telephone calls made from Mr Morris' home phone showed he had not been out for the whole day.
Mr Morris said he could not explain the calls made to his parents and the bakery where his partner Mandy Jewell worked.
The prosecution claim Morris did not approve of Ms Power's friendship with Ms Jewell and nursed a "strong antipathy" toward her.
The court heard that on the day of the killings, Mr Morris spent the afternoon and evening drinking. Mr Morris said he argued with Ms Jewell at the New Inn, in Clydach, and left alone between 2315 BST and 2330 BST.
He said he did not go to the couple's home in Craig-cefn-parc because he "knew they would argue," but instead set off towards his parents' home in Gendros, Swansea.
Mr Morris said he turned back because it started raining and he was "getting soaked" and arrived home some time before 0300 BST.
Mr Morris denied going near Mandy Power's home in Kelvin Road and said the first he knew about the murders was the following morning.
He said: "Mandy Jewell came into the bedroom crying."
The prosecution alleges that 34-year-old Mrs Power, daughters Katie, 10, Emily, eight, and Doris Dawson, 80, were killed during a "murderous spree" at their home in Kelvin Road on Sunday 27 June 1999.
At the beginning of the trial in May, Mr Harrington claimed Mr Morris probably exploded into a rage after his sexual advances were spurned.
He said Ms Power had been attacked in three bedrooms of her home, suffering 38 injuries. She had also been sexually assaulted.
Both children had suffered devastating head injuries. Their disabled grandmother was killed in her bed.
Mandy Power's sisters and brothers were in court.
They arrived along with Alison Lewis, the former policewoman who was Mandy Power's lesbian lover and who was originally arrested on suspicion of these murders but was released without charge.
Also present were members of Mr Morris's family.
The trial was adjourned on Friday until the following Monday because the defendant was unwell.